XTB, reliablity, etc.

First, I want to clear up a misconception. The X10 signal sent down the powerline IS essentially RF. It is a 120KHz carrier that is switched on and off in 1 mS bursts. The XTB sends the boosted 120KHz carrier over the powerline like any other plug-in X10 device. It does not rely on any RF transmission through the air.

What you say about the power distribution system being dynamic is very true. It is also a very complex problem sending 120KHz over wires designed to carry 60Hz power. It turns out that the wire lengths and distributed capacitance in a typical household distribution network can result in a multiplicity of resonant circuits at 120KHz. That will cause peaks and nulls throughout the network even neglecting the impact from various noise sources and signal suckers. Any automation system that sends encoded data over the powerline as an RF carrier must somehow deal with these issues.

The XTB takes a brute force approach, and just pounds out a stronger signal. It has enough power supply behind it to deal with a few signal suckers. If you have a couple of wired X10 sources at the same location, their outputs can both be boosted by a single plug-in XTB.

There is also the XTB-II, which is designed to be installed adjacent to the electrical distribution panel to drive both phases directly. It has built-in TW523 emulation for a high-end automation controller. And the new firmware upgrade includes a repeater function so that all standard X10 signals received by the built-in X10 decoder can be re-transmitted in sync with the second copy.

To answer your other question regarding monitoring what is plugged in, I don't do that. Known problem sources have been isolated with filters. My approach has been to insure there is sufficient signal level on all X10 circuits so it doesn't matter what is plugged in - even an occasional signal sucker. That works for us because there have been no recognized X10 control problems in the last several months.

Jeff

I'm not sure you cleared that up. I think the OP saw the TM751 plugged into the XTB and misinterpreted that to mean that was the only thing that it will boost. It will boost any X-10 transmitter plugged into it.

I understand what it does. It just doesn't help much for wired devices that send x10. It only helps for things you plug in, which are RF transponders and PC/microcontrollers. So, to actually use the XTB, you will end up moving all of the user inputs to RF so they can be relayed through a transponder to the XTB. Wired transmitters such as light switches won't benefit. Even if you pop open the XTB and wire it in-line with a wired controller, you'd need one at every location you want to put a controller, which would be expensive and difficult to install.

So an XTB solution is really about eliminating x10 signals generated directly from user input, and using RF instead.

That was actually the TW523 that the XTB was originally designed to interface with. But it does look like the TM751, and someone might assume it only buffers RF signals.

I thought a bit about this after my earlier message, and it sounds like the OP arranges his filters by trial and error until he finds a configuration that works. Unfortunately, that is likely to be just over the minimum acceptable signal levels, and the next widget plugged in could cause a problem.

To get a reliable X10 system (and I mean RELIABLE), one has to do some homework. The fact that adding a filter doesn't seem to change anything doesn't mean that device is not causing a problem. It may not be enough by itself, but can be when something else is added on the same circuit.

We know most computers will cause problems, so they all should have filters. Compact fluorescents are a gray area. Some work fine, but others can be a problem, and will need a filter. Some electronics, like our old Sony TV and our APC UPS are major signal suckers, and need filters. The best way to identify these is to use a X10 signal level meter like the ESM1 to measure signal levels throughout the house. I use a palmpad to trigger commands from a RF transceiver near the main controller. Monitor each AC receptacle with a possible problem device either plugged in or not. If there is ANY change when the device is either plugged in or switched on, than that device should be filtered. No maybe. You want reliability.

Then go around to all receptacles. If any read down around 100mV, that circuit is a candidate for problems. Locate any remaining signal suckers on that circuit. If none are found, then the overall signal level should be increased. That's why I built the XTB in the first place. We have one central circuit with nine X10 devices on it, including several transmitters. That circuit read only 100mV. Everything still worked, but was marginal. Adding a XTB down at the breaker panel raised that circuit up to 1V, so I don't have to worry about any random device being plugged in.

There are other things that can be done to make the house X10 friendly, like move all X10 circuits to the same phase. We also installed the small Leviton 6287 filters on all X10 ceiling can circuits that could possibly use CF bulbs. I didn't bother testing the bulbs first because I was after reliability.

If one takes the time to set the system up properly in the first place, then there is not the continual debugging whenever the next electronic widget is added. Do the homework, and the system works. Recently my wife said one light didn't come on when it should have. It turned out that after several years the bulb finally burnt out. I guess X10 can't fix everything.

Jeff

The XTB works with any plug-in X10 device like the maxicontroller, CM11A, TW523, or RR501. Most light switches are receivers only, and they will receive a stronger signal for more reliable control when using the XTB. You are correct that the XTB was not designed to boost the output of wire-in transmitters like the Leviton 16400.

The XTB and XTB-II are both intended to boost the output of your primary automation controller to boost signal levels throughout your house, and increase reliability. The XTB cannot boost the output of remote transmitters. However, the repeater function of the XTB-II can do that if the remote transmitter can get an acceptable signal to the XTB-II.

Jeff

Thanks, Jeff. That was interesting. I have mostly worked by trial and error, trying to identify appliances that cause signal loss.

b.c.

Jeff Volp wrote:

No, you still haven't grasped what it does. It amplifies the PLC (i.e. PowrLine Control) signal of any X10 PLC transmitter plugged into it.

Any receiver, including light switches, will benefit from the stronger control signals. If you have switches that also transmit (some Leviton, some Switchlinc) their output will not be amplified but that's usually an insignificant part of the "usual suspects" when it comes to X-10 problems. There's a dearth of software that does anything with the feedback signals from such switches.

Not even close. I think you lack an understanding of the fundamentals and your X-10 system performance likely suffers as a result.

I understand the technology fine, Dave. Get over yourself.

Can you spell this out for me Dave?

User pushes a button on a wired device that generates x10 signals. How does the XTB help?

The answer is, it doesn't. It only helps if the user pushes a button on an RF transmitter, that will be relayed through the XTB. If the signal doesn't go through the XTB, it isn't doing anything.

b.c.

Dave Houst>

Which doesn't help with keypadlincs, 2-way switches, tabletop controllers, or any other control a user is likely to have around the house. Very small percentage of X-10 users likely have a master control pc/automation controller/security panel. Most people have a few plug in controllers around the house, maybe some tx/rx 3/4/5 way switch circuits. XTB won't help with those unless, as Brian rightly pointed out, one was wired in to every one of those control points.

Now, Jeff's repeater/booster version, on the other hand.. :)

In my case, I distributed some Maxicontrollers around the house and fed them into (4)XTB's, as well as a CM11A and some TM751's. Most of the time, we use minicontrollers in the room where lights are located. Even unboosted, they managed to control the local lights just fine. I rarely need to control a device outside a room that I am actually in except at bedtime or when I am entering or leaving the house.

The XTB comes to play in the bedroom or at the front door (two places I have XTB/Maxi combos) where I can push an ALL OFF with the certainty that every light in the house will go out. I know that commands from CM11A are going to get through since that's attached to an XTB (along with a Maxicontroller and a TM751 via a 3-way extension cord). I also like the ability to be able to flash every light in the house simultaneously, and the XTB makes that possible as well.

No, it's not perfect, but it's light years ahead of where I was before. Ideally, every X-10 transmitter would be hooked in through an XTB but that's not practical either spacewise or moneywise for me. I completely understand your frustration. If Jeff were not constrained by physics I would like the XTB to be a plug in the size of one of the old single unit surge protectors (or better yet, a little device you clip on transmitter's powerline like a ferrite bead), however, he is limited by a number of constraints and so they are not cheap and not small. But having four of them is very much "good enough." The big problem of not all units responding to the nightly "lights out" has been solved elegantly by the XTB.

I have even been thinking of pulling a series of outlets for nothing but plug-in controllers that would feed into some centralized, rack mounted XTB's. I would probably have to cut the standard power plugs from such controllers and use connectors that would make it impossible to plug the Hoover vac into the XTB, but the big issue there is the limitation on how many watts of load can be plugged into each XTB. Right now I am using three controllers apiece (and in one case, four) and the total load shown on my Kill-o-watt meter was way below what I believe to be the XTB's 15W plug-in device limit. Jeff will hopefully correct me if I am wrong.

As for glowing testimonials, I really do find myself saying "Thank you Jeff" when I hit the ALL OFF button at my bedside and I hear the satisfying click of *every* appliance module actually obeying the command. It certainly wasn't that way BEFORE the XTB arrived on the scene.

That reminds me of another way in which X-10 is really rather elegant. The ALL OFF command affects all modules virtually instantaneously, without any queuing issues, acknowledgment problems or network propagation delays. As long as X-10 keeps doing that one thing so well, it will be at work in my house.

-- Bobby G.

Actually, for most people this isn't as much a problem as it may seem. We have a bunch of wired Leviton 16400 4-button switches that we use to trigger macros in the Ocelot and to directly control lights. All that stuff works fine without XTB boost. Similar for the minicontrollers and maxicontrollers spread around the house. In most cases these control devices on their own circuit, so needing a boosted signal for distribution throughout the house is not important.

Actually, most people who have given me feedback on the XTB performance do use it to boost the output of their master controller. Including not only high-end controllers using the TW523, but also the CM11A and CM15A, a large percentage of X10 users fall into this category.

Jeff

Well, at least a large percentage of XTB users. As one might expect! :-P

Anyway, if I ever have X10 problems, I'll sure be buying one. I use an ocelot!

Or the floodlight, or two-way devices, or...

How well does the repeater function of the XTB-II work with things like micro-dim, and as compared to other repeaters frequently castigated here and in other X10 discussions?

I'm considering an XTB, but I am far from certain that signal strength is the significant factor behind my currrent troubles.

sdb

I have a testerlinc. It shows a silly "quality" number for X10 traffic, and an equally silly "120khz activity" number. Yet it has been incredibly helpfull isolating noise sources. Other things which I suspected have shown no testerlinc differences with or without a filter, so I "assumed" they are OK without.

Is that a flawed assumption?

Mine are running thru UPS's, and one site caused a large problem, the other no apparent problem.

Yup. I relocated my problem ones so they'd all be together. Cheaper to filter one spot, but again with no evidence to the contrary, I did not filter them all (yet).

Probably should have one of those, but another nearly $100 is also distaseful.

sdb

I believe the XTB-II will work the same as other repeaters in that regard.

Like the TW523, the XTB-II sends digital data to the automation controller in sync with the second half of a standard X10 message. When the repeater function is enabled, it will also transmit those bits to the powerline at the same time.

Remember, the XTB-II is intended to be the powerline interface for your automation controller. So it will transmit those bits exactly as received without activating the repeater function. That is only used when receiving incoming messages from other X10 transmitters.

So, if your automation controller is capable of sending micro-dims, the XTB should transmit those to the powerline exactly as received.

Jeff

Unfortunately, the SignalLinc doesn't appear to measure signal strength. I don't think the X10 quality number is a good indicator of signal strength until it becomes marginal. So, this instrument may not be that useful for finding signal suckers. However, that 120KHz activity number may be a good tool to identify noise sources.

Jeff

The 20+ volt signal of the XTB kills an *awful* lot of different demons, from noise to signal suckers. I would feel comfortable saying that *anyone* using a centralized controller like a CM11A or a TW523 will benefit from using the XTB. I just ordered four more because now that I've gotten used to a few of the turbo-charged controllers I want all the key controllers to be on XTB's.

-- Bobby G.

In my case even this doesn't work, because a particular room may be fed by several different power circuits. I thought this was rather common. I typically see outlets and lights on different circuits, and circuits tend to follow walls rather than rooms. A controller wired at an entry way (as a light switch) is not on the same circuit as any of the outlets it might need to control.